The options/possibilities are almost endless (within the constraints of the graphic file). Once I figured out the sequence of the PC's compressor VU meter I made it digital - numbers instead of needle.
 
As far as keeping a graphic within the confines of it's original size, that's not always necessary. Each graphic behaves differently but you can experiment with resizing one and see what happens. Sometimes the results are quite nice.
 
Just to clarify, Sonar positions a graphic according to it's top left corner, so any size changes have to be to the right and/or down. You cannot extend a graphic to the left or higher than it already is. Unless... there is empty space (transparency) that allows you to move an image within the graphic closer to that corner.

Anderton
Another knobby technique I've used with FX chains is to apply a gradient from the initial knob rotation to the end. For example a knob can get brighter as something gets "louder," or you could have a panpot go from red (left, for port) to green (right, for starboard) as you rotate it.
 
For an example of how this can be done subtly, check out FX Chains > Anderton Collection > Processors > Graphic EQ. The knobs get more red as you boost, and more blue as you cut. For an over-the-top example that possibly indicates mental issues , load FX Chains > Anderton Collection > Drums > Psychedelic Drums.

Ooooh... more ideas for my next theme adventure.    Thanks!
 

...apply a gradient from the initial knob rotation to the end. For example a knob can get brighter as something gets "louder," or you could have a panpot go from red (left, for port) to green (right, for starboard) as you rotate it.

 
Does TE allow you to change the Arpeggiator value sliders like that? In X1-3 Duckbar discovered they had different locations for Minimum and Maximum allowing you to blend the 2 colors as the value increases. To my knowledge, the Arp sliders were the only sliders capable of that.